Method and apparatus for forming metal closures



Aug. 10, 1937. `J w s 2,089,518

METHOD AND APPARATUS FOR FORMING METAL CLOSURES Filed May 19, 1933 2 Sheets-Sheet l Aug. 10, 1937.

J; J. WILLIAMS METHOD AND PPARATUS FOR FORR'EING METAL CLOSURES Filed May 19, 1953 2 Sheets-Sheet 2 maid/7776 mama-Au o, 1937 UNITED STATES PATENT 'OFFICE a claims. (eina- 48) 4 The invention relatesto a method and apparatus for forming' metal closures, particularly metal closures provided with an incurled bead and lugs which are hidden or substantially hidden from view. The article produced by the present invention is not claimed in the present application.- A particular cap or closure, produced by thepresent invention, is disclosed for the purpose of making the invention clear; but n such cap is 'not claimed inthis application, and

as will'appear hereinafter the method and apparatus of the present invention are capable of producing dflerent caps.

One of the objects of the invention is to provide a method and apparatus by which, 'in a single pressing operation,.an ordinarycylindric'al blank is' converted into a completed cap with an incurled bead and lockinglugs.

Anotherobject of the invention is to provide a E method and apparatus by, which' parts of 'the blank will be positively curled inwardly, while other partsof the blank will merely be drawn inwardly, and to a lesser degree, by the positive Inward curling of the other parts.

' Another object of the invention is td'provide a method of forming lug caps by which the production is greatly facilitated, with "a consequent 4 lower cost; and to provide an inexpensiveand very simpleapparatus by which the method can be carried out; V

Various other objects and advantages of the invention win be apparent to those skilled in the art ofmanufacturing metal caps, from the following detail ed description when taken in con'- nection 'with the accompanying drawings; in

which, V Figure. 1 is a Vertical sectional viewvof the mechanism, 'showingthe conventionalblank in ,place ready'to be acted upon by the die; the parts r being in raised position above the blank. and the section of the ring 'being 'taken through the portions where theriugs are formed.

Figure 2 is a-view similar to' Figure 1, 'but with 'the'parts having been moved down to cap form-I ing position.

Figures is a view similar to l 'i gire'z, but with v 4 the section of the curling ring being taken through the portions which form the incurled Figure 4 is a perspective view of the curling ring removed from' the apparatus. V

Figureisa :z ticviewillustratingthe formation ofthe 'ineurled bead and lugs.

Figures 6, 7 and 8 are enlarged fragmentary sectionalviewsthroughacapintheprocessof being formed. and ilustra ins: some of the in the formation thereof and Figure`9 is a perspective view of a completed cap.

, n The preferred apparatus will now be described 5 in detail, but it .is to be understood that the present invention is in no manner limited to the specific apparatus shown and' described. Nu-' merai l refers to an ordinarycylindrical shaped blank, formed in the usual manner and placed, 10

by' any desired means, upon the plug 2. A resiliently mounted centering plate (not shown) ,is preferably associated with the plug. This plug is mounted on the die block 3. which is secured to the bolster plate of an ordina punch press 15 (not shown), or to any othr'desired machine. Numera 4 refers to the ring holder, which is clamped to the ram of an ordinary punch press 1 (not shown), or to any otherimechanism providing a' reciprocable movement. This 'recip'ro- 20 cable ring holder carries several parts, which will now be described. Numeral 5 indicates a guide or centering ring, which is carried by the holder, and which has asn'ug fit'with the cap blank;' the lower end of this ring being preferably fiared, 25 as indicated by numeral 6. The curling ring or die is referred to by nu'neral and it is provided with an annular curling gro'ove 8, which is semicirc'ular in cross-section. This curling groove is continuous except 'at the points where the lugs are to be formed,- and at these points the .die is provided with cut-out portions 9. Thefunctions of the curling groove and the lug-'forning cutout portions will be described hereinafter., Numeral I' refers to a clamping and ejector pad, 5 provided witman upwardly extending stem' |l. Arranged about the upper end ofthe stem' isa er '3 secured inplace by a cotter pin il or by other suitable means. Within the holder 'there is arranged about the stem I' a heavy coil spring "5: the upper endofthe' spring resting against the holder and the lower end thereof resting 45 against a washer '6.

` The invention will be better understood by first' describing the operation of the parts without de -v scribing the particular eifects'produced on the cap blank, and then describing' the manner 'in 50 'which the die forms the incurled head and the lugson the blank in a single operation.

v As'the ram of the press descends the guide or centering ring 5 fits snugly around the cap blank i, thereby not only accurately centering the blank 5 with respect to the descending die ring, but also supporting the skirt or fiange of the blank to prevent any outward bulging of the skirt' when the die acts on the rim or edge of the blank. Further downward movement forces the pad 'l' firmly against the insidetop of the blank thereby holding the blankflrmly seated on the plug 2 during the pressing operation. The pad IO now remains stationary, but the curling ring or die 'I continues oto descend against the pressure of spring '5, to the desired position' to produce'the desired efiect on the cap blank; the parts in their lowered or cap-forming position being shown in Figures 2 and 3. The ram now rises, and during the first part of the upward movement the pad o is held stationary 'against the cap by the spring '5. The cap is thus moved from the die but it may still be within the centering ring 5 by reason of thesnug fit between this .ring and the cap. As the upward movement of the holder and ram continues the die ring 'I and washer '6 come together and'then the pad rises with the holder, and during the continued upward movement the stem 'I of the pad l' strikes a stop (not shown) on the press. This causes the upward motion of the pad to be stopped, while the other parts of the upper die, including the centering ring 5, continue to rise, the spring -|2 being compressed. This action causes the cap to be ejected from the centering ring, and it then falls into a container .(not

shown). another cycle of operation.

Having described the purely mechanical operation of the parts, I shall now describe' in some detail the effects produced upon .the cap blank by the descending die, and the method by which the inturned curl and the lugs are formed in a single pressing operation. .When the .die first comes into contact with the rim or edge of the cylindrical blank, the curling groove 8, which is a complete circle, and which is substantially semicircular in cross-section except where the' lugs are formed, causes the entire rim or edge of the blank to start to curl inwardly, as indicated by numeral Il on the diagrammatic Figure 5. The lug forming portions 9 of the die are of peculiar construction. The outer part is curved on the same curvature as that of the curl- ,ing groove and conforms exactly therewith, as clearly shown in Figure 4; but it will be noted' that the curvature of the curling groove is completed to a semicircular form, while the lugforming portions curve in only a very slight distance, preferably just enough to start the metal to curve. portion may be varied as desired. The tops of the cut-out portions extend inwardly and upwardly from the point where the curved surface ends, in the specific form'illustrated herein; but

it will be understood that this inclined portion may be entirely omitted, as it has no eifect on the operation. In other words, the die could be cut away completely at the points where the curvature ends. so that there would be an open space 35 over the metal where the-lugs are being` formed, x

except for the slight curved portion.

As the die continues 't descend, the curling groove, which is substantially somicircular in cross-section, positively'causes the metal of the o blank to continue itscurving until it makes a The parts are now ready to start Of course the extent of the curved:

numeral 2" is approximately the usual position I prefer the lugs to assume. Of course Figure 5 does not -illustrate the actual shape the metal takes in forming the-lugs by the single pressing operation, as `it is intended merely to illustrate diagrammatically how the rim of the blank isforced to form an inside curl while the cut-cuts permit metal at those points to lag behind and be drawn down by the curled portions, as distinguished from being positively forced to a particu-' lar position. The exact structure of the lugs .thus formed. will be better understood by reference to Figures 6, 'l, 8 and 9. Figures 6, 'I and 8 show some of the steps in the formation of a lu'g, and Figure 9 shows a completed cap. Figure 6 shows the conventional 'plain cylindrical cap blank before the die has been brought intocontact with it. In Figure 7 the' cap is in process of `formation, and it will be noted that the bead' has already curled up into a' substantially semicircular form, as indicated by numeral 2', while the lug forming portion 22 is lagging behind; It will also be noted that the lug formin'g portion is connected to the partly curledbead by somewhat triangular-shaped portions 23. 'In Figure 8 the die has descended far enough to complete the specific form of cap shown in Figure 9. By reference to Figure 8 it will be noted that the curled portion 2' has been forced to a position substantially completing a circle, while the lug-forming portion 22 while still lagging behind yet has been drawn to a position where it inclines slightly upward toward the top of the cap. The lug' and incurled bead are connected by the triangular portions or gussets 23, The present invention is not limited to the making of any, specific cap, and the cap as an article is not claimed in the present application. Nevertheless it will be helpful in understanding the present invention, to`

describe certain other efi'ects which are produced A upon the blank by the single pressingoperation in completing a specific form of cap which is shown in Figure 9. v

While the incurled bead is being formed and while the lug-forming portions are being drawn inwardly and downwardlyby the incurling of the bead, an arch or depression is formed in the bead where the lugs are located, as indicated by numeral 24, Figure 9. These arches or depressions terminate in slight bumps 25, which rise a very slight distance above the normal plane of the bead. It is to be noted that these arches are not fiat transversely but are curved transversely, as shown in Figure 8. In this figure, the'section'is taken at the center of the arch, and one of the slight humps 25 is shown in elevation. As the cap per se is not claimed here, it need not be fur-` ther described; it being sufiicient to state that this arch is formed by the method and apparatus herein disclosed. and that the cap thus produced, witha lug havingaportion'hichisarchedin one direction and the arched portion being curved transversely, provides strong lug formation. If the die is' caused-to decend 50 lugs.

still further, thereby causing the lugs to be more sharply inclined upwardly to an almost Vertical position, the arches and humps will be drawn out of the lug formation, thereby producing a cap having its rim smooth and curved throughout,

when viewed from the exterior.

While the invention has been described in great detail, yet it is to be clearly understood that the present invention is not in any respect limited to details shown and described, but relates broadly to a method and apparatus for forming metal caps in which the bead is positively curled inwardly and the lugs lag behind and are drawn inwardly by the incurled portion, and the cap being completed from a conventional cylindrical blank by a single pres'sing operation.

Having fully described my invention, claim is:

1. The method of forming a metal'c'ap from a cup-shaped blank in a single stroke of a die which comprises curling an inside bead on the skirt by the pressure of a die, and 'by the samestroke of the die causing the inwardly curling head to draw inwardly adjacent portions of the skirt to form lugs. V

2. The method of forming a metal cap from a cup shaped blank in a single stroke of a die'which 'comprises curling inwardly certain portions of what I r the skirt by the pressure of 'a die and by these 0 curling in portions dragging inwardly -lagging portions under the same die stroke, to formiugs. 3. The method of fprming a metal cap from a cup-shap'ed blank which comprises the forming of inwardly extending lugs at intervals by curling inwardly 'other portions of the blank skirt, in-a single stroke of a die.

4. The method of forming a metal cap from a cup-shaped blank which comprises the forming of inwardly extending lugs at intervals without V 40 the direct application of`pressure thereto by directly applying pressure to otherportions of the blank skirt to form an incurled head, in a single stroke of a die.

5. The method of iorming ametal cap which comprises engaging a die with the raw edge. of the skirt of a cup-shaped blank andcausing said edge to be cu'rled inwardly, and then further curling portions of the skirt to cause the raw edge of other portions to be dragged inwardly to form 6. The method of forming a metal cap which solelycomprises curling inwardly the skirt f a 'cupshaped blank and by this inw'ard curling causing the raw edge of certain portions 'of 'the skirt to be dragged inwardly to iorm luga- A 7.- The method of iorming a metal cap which comprisesengagng -a die with the raw edgeof the skirt of a. cup-shaped blank and curling inwardly portions of the skirt, forming lugs which; i

project inwardly of the inwardly curled portions,

and forming depressions in adjacent the lugs. V

8. The methodoi forming a metal 'cap' which comprises engaging a die with the raw edge of .the skirt of a cup-shaped blank and curli'ng inwardly portions of the skirt, forming lugs which project inwardly of the inwardlycurled portions.

and forming' humps with a depression therebetween in the edge of the cap adiacent the lugs.

the edge of the cap 9. The method 'of forming a metal cap which comprises engaging a. die with the raw edge of the skirt oi' a. cup-shaped blank and curling in-.

'wardly 'certain portions of the skirt, by this in-' ward curling causing other portions of the skirt to be dra ged inwardly to form Inga-and forming depressions in the edge of the cap. adjacent the lugs. V A

10. The method of forming a metal cap which comprises en aging a die with the .raw edge of the skirt of a cup-shaped blank and curling' inwardly certain portions of the skirt, by this inward curling causing other portions ofthe skirt to be dragged inwardly to form lugs, and forming-humps with a depression therebetween in the edge oi' the cap adjacent the lugs.

11. An apparatus for forming metal caps in'- cluding a die having means for engaging and inwardly curling the raw edge of the skirt ofa cupshaped' blank, and means on said die causing portions of the skirt to be drawn inwardly, from positions within the boundary of the skirt, by the incurling head to form lugs.

12. An apparatus for forming metal caps including a die having an ann'ular groove to curl inwardly the edge of 'a cup-shaped blank to form an incurledbead. said annular groove having cutout portions at intervals in its inner wall only to permit portions of the blank to be drawn inwardly to form lugs,

r 13. An apparatus for forming metal caps ineluding a die having an annular groove of substantially semicircular cross-section to curl in.- war'diy the edge of a cup-shaped blank to form' 'an incurled head, ,said semicircular groove having a continuous wall, and having its inner wall cut away at intervals', to permit portions of V the blank, the die being cutaway at other por- 4 tions. thereby permitting the raw 'edge of the blank at these points to be freely drawn inwardly to' 'form lugs, the angle the lugs assume with respect to the skirt of the cap varying in accordance with the extent 'of the curvature oi the head 15. An apparatus for forming metal caps, comprising a single die. means on said die for curling inwardly .the raw edge of a cup-shaped blank, and other means on the die for causing' portions of the blank to be dragged inwardly, to form lugs.

16.. An apparatus for forming metal caps, compris'ing a single die, means on said die for forming an incurled 'head on a' cup-shaped blank, and

means for causing portions ofthe raw edge of the blank to be dragged inwardly, to form lugs.

17. An' apparatus for formingnetal c'aps'ineluding means for forming an incurled bead on a cup-shaped-blank, and means for causing portions of the raw edge of the blank to be dragged inwardly,toform lugs. V

18. The method ot forming a metal cap which comprises exerting curling pressure on the raw 'edge of the skirt of a cup-shaped blank to give only'a slight inward curl throughout' the edge, and after this slight curling relieving the curling pressure at certain points only, to form lugs. j

JOHN J.

DISCLAIMER '-2,089,518.-John J. Williams, Whee W. Va. Mmon AND A mu rus mon Fonw METAL CLOSUREB. atent dated August IO, 1937'. Disclaimer filed December 1, 1937, by the assignee, Hazel-Atlas Glass Company. Hereb enters disclaimer to claims. 12 end 13 in said patent.

'[ Gazette January .4, 1988.]

DISCLAIMER 2,089,518.-Jo7m J. Williams, Wheeling, W. Va METHOD AND APPARATUS FOR FORMING METAL CLOSURES. Patent dated August 10, 1937. Disclaimer filed December 1, 1937, by the assignee, Hazel-Atlas Glass Company. Hereby enters this disclaimer to claims 12 and 13 in said patent.

[Ofiicial Gazette January 4, 1938.] 

